Pages Menu
Categories Menu

on Aug 24, 2011 in Friday Thoughts

The Exposure Equation

My posting on The Crop brought in a flood of emails, not about cropping but about exposure. The “Don’t give yourself the option of fixing in post” seemed to, ah, intrigue folks. The idea of getting the exposure right in the camera. I’ve written about that many times here on the site. I’ve posted the Teddy Bear exercise which I invented (for film 25yrs ago) and understandably, exposure still eludes many. In Captured, I wrote and illustrated nearly 50pgs on this one topic in an attempt to explain how I approach exposure. I’m hoping this excerpt will open some doors to how I expose and better yet, get some to buy Captured to get the whole explanation. But the bottomline, when I go click, the exposure that I want to communicate what I’m feeling is captured.

“Seeing” light, “feeling” light is such a challenge yet so essential. Getting to the point where you point your lens at that Alaskan Range, know how much exposure compensation to dial in a click takes many clicks before that one from over the years but shooting digital cuts down the learning curve and time by lifetimes if you use it by thinking! Just looking at your own digital images, looking at the metadata and learning from what you did in the past can greatly impact the clicks you make tomorrow. Those images you like, how did you deal with the exposure? Those images you don’t like, how did you expose for them? Remember both so you can repeat the successes and avoid the failures. (Which are still a learning opportunity so don’t be afraid of failure!)

You have a feature on your camera (available on nearly all cameras these days) called Highlight Warning. I affectionately call it Blinkies because that’s what they do. Remember we have a five stop range of light that we can capture with one click (HDR doesn’t work for wildlife). When you have more than five stops of light, when you have 5.1 stops of light, you’re outside the range of the camera’s single click ability to hold detail in highlights and shadows. With the Blinkies turned on, those highlight areas in your photograph that are outside the five stop range literally blink at you, black then white. You have to use your LCD (a good reason to look at it) and have the Highlight Warning turned on in your menus and active on your LCD to see them. When you’re trying to learn light, Blinkies will teach you instantly when you are outside that five stop range. But they can help your photography even more than that! They show you exactly where in your photograph you have lost that highlight information. That’s big time important!

What does the mind’s eye crave first in a photograph? Yeah, light and bright. If you look at those blinkies as not only a possible exposure problem, because blinkies are not necessarily bad, but as something the mind’s eye is guaranteed to latch onto, you can then make the decision of if they are good or bad, not for exposure sake but visual communication sake. It is amazing that your digital camera cannot only teach you about the range of light, but also predict where the mind’s eye is going to go in your photograph and visually show that to you. Wow!

Let’s say you’re photographing that Great Egret, an all white bird. What if you see a couple of small blinkies on its body? Is that a good or a bad thing? The knowledge and sight of blinkies doesn’t mean all is lost. In this case the subject is all white. Is the loss of some detail in that white messing with what you’re communicating visually? Is it taking the mind’s eye somewhere you don’t want it to? I don’t have that answer, you will have to answer those questions when you have it in the viewfinder and on the LCD. Half the battle is knowing what question to ask, your camera can help you there with blinkies. Loosing some detail in a white subject I don’t think is the end of the world though so personally, more than likely I wouldn’t worry about a couple of small blinkies. You have to make that call but at least, you now have a tool to use and a thought process to employ to make an informed decision. Just remember in this process you don’t forget to ask what’s the subject.

Here’s another way to think about it (because you do have to think about it). If you write a paragraph of words and then from that paragraph take away 20% of the words near the beginning of that paragraph, would someone understand what you’re trying to say? Now imagine your photograph between the X & Y axis being 100%. If you don’t have information in 20% of that top area (like blown out clouds) because it’s information lost (or anything else visually distracting), the blinkies are going wild, will someone understand what you’re trying to say visually in your photograph? Don’t lose sight we are visual communicators and one of our key methods of communicating visually is with light!

When you start thinking about light and the levels of light in your photograph that you control via exposure in this way, you start to feel it in your photograph. The photograph of the White Ibis, if you look at the butts of some of them (bird perverts), you’ll notice there is NO detail, it’s just paper white. When I looked on the LCD to do a visual check because white subjects in the shade are not a great light situation, I could see blinkies. Yet, the photo is in the book and the image is a favorite. Why?

The mangrove forest in which the ibis are standing in front of is a real busy one, real busy. Those roots go every which way and instantly grab the eye’s attention. Standing in the water and looking through the viewfinder, they came glaring in. But where are those roots in the photograph? They are in the shade and lost because of the exposure range. What’s the subject (there’s that question again)? The subject is the line of Ibis and their reflection, White Ibis in mixed light. It’s not one individual Ibis. What’s the light range between the background, the roots and the subject, the Ibis? You think, 7, 8, 9, 10 stops? How many stops do we know the camera can capture in one click? Five right. So then knowing the meter is going to sacrifice the shadows (why, because of that light and bright thing the mind’s eye craves), with that kind of light range, the roots in the shadows will go black making their busyness disappear literally in the shadows and creating a background that makes the ibis blaze off the page. That’s feeling the light and letting it work for our photography. I exposed with my normal -1/2 dialed in. Normal?

What do I mean by “normal” exposure compensation dialed in? How many of you shot film? Do you remember how we would take Kodachrome 64 and rate it at ASA 80? Do you remember why we did that? Because that underexposure of 1/3 stop saturated the colors and made the shadows go a little deeper black. For those same reasons and some more (like protecting some highlights), color saturation and darker shadows, the majority of the time I underexpose by 1/2 stop. That’s all that was done in this case but that made those roots a little darker, the red in the bills a little more vibrant and possibly brought one or two of the blinking pixels back within five stops.

Light, mind’s eye, exposure, they are all so intertwined I don’t really believe they can be separated. And when you think of these as all ways of expressing emotions, I don’t think they should be separated. For some though this “touchy-feelie” approach to combining shutter speeds and apertures just won’t work when it comes to making an exposure (just gotta have those numbers). I understand that but guess what, since I don’t use that method, I can’t begin to address that side of exposure. I think the last thing the world needs is another technically perfect photograph. What the world needs are more photographs with passion. You have to decide if the system you have brings to life the drama you see and if it does, disregard this conversation. I bet though you might find some wiggle room where there is something in my images you would like to incorporate into yours. If that’s the case, you might just want to try feeling the light. The worst that can happen is you delete the photograph, right? And the best thing, your exposure problems disappear!